<!doctype HTML>

<style>
#parent {
  width: 100px;
  height: 100px;
  background-color: lightblue;
}
#child {
  width: 50px;
  height: 50px;
  background-color: blue;
  will-change: transform;
}
</style>

<div id="parent">
  <div id="child"></div>
</div>

<script src="../../resources/run-after-layout-and-paint.js"></script>
<script>
runAfterLayoutAndPaint(function() {
  document.getElementById("parent").style = "height: 500px;";
  parent.postMessage('done', '*');
});
</script>

